"[The man] whispered and said, 'I'm going to kill you,' " one sister said of the attack

http://player.ooyala.com/iframe.js#ec=F0c29xdzqYiGnZ-2Ju-VoThDuOfTAVPT&pbid=3ce6404476914e86994d87aac3e4391bWith tears in her eyes, a Salt Lake City, Utah, woman is calling a local officer “our angel” after reportedly saving her and her sister by shooting and killing a violent home invader on Wednesday, she told local TV station Fox 13.

Bre Lasley told the station that the suspect came through her bedroom window that night armed with a knife.

“He whispered and said, ‘I’m going to kill you,’ ” she said.

Robert Berger, 48, has been identified as the suspect in that case, Salt Lake City Police Department Lt. Michael Hatch tells PEOPLE.

Berger was fatally shot once in the head in the Lasley’s home, Hatch says.

“When the officer arrived, the victim’s sister came out and told the officer that her sister was being stabbed,” Hatch says.

Once the man was in her home, Bre told Fox 13 a struggle ensued.

“[The man] put his left arm over my mouth and started punching me in the stomach and he said, ‘You cooperate with me or I’m going downstairs to get your little sister,’ ” she said.

Lasley’s sister Kayli heard her anyway, and came to her sister’s defense, they said.

“We were punching him and fighting as much as we could and he was doing the same to us,” Bre told Fox 13.

Bre said that when the man went after Kayli, “strangling her up against the wall,” Bre tackled him and her sister went for help.

Bre was stabbed multiple times, in the leg and abdomen, before the unidentified officer arrived. The man ignored commands to drop his weapon, Kayli told Fox 13.

According to the Deseret News, Berger had served more than 14 years in prison, including for aggravated robbery, and was released from the Utah State Prison on Sept. 15 after being previously paroled.

Berger is accused of attempting to enter another home earlier that same night, but was unsuccessful, Hatch tells PEOPLE.

According to the Deseret News, witnesses said a man, allegedly Berger, tried to break into a home down the street from Lasley, but the occupants drove him away.

A woman in the home, armed with a lamp, “pretty much jousted him out the window,” her boyfriend told the paper.

It was while responding to that call that the officer discovered the attack at the Lasley’s home, according to the News.

The officer has been placed on administrative leave pending an investigation, Hatch tells PEOPLE. The Unified Police Department, a neighboring law enforcement agency, has assumed the investigation, as is standard procedure, he says.

Neither the officer’s name nor information on a possible motive have been released, Hatch says.

The Lasley sisters are now staying with their parents, according to Fox 13. Bre told the station, “Whenever I close my eyes, I seem to have that image of him coming into my room.”

PEOPLE did not immediately receive a response for a request for comment from Unified PD.

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